Field
Various features relate to an integrated device that includes stacked dies on redistributions layers.
Background
FIG. 1 illustrates a conventional integrated package 100 that includes a substrate 102, a first die 106, a second die 108, a first set of solder balls 116, a second set of solder balls 118, and a third set of solder balls 120. The first die 106 is coupled to the substrate 102 through the first set of solder balls 116. The second die 108 is coupled to the substrate 102 through the second set of solder balls 118. The third set of solder balls 120 is coupled to the substrate 102. Typically, the third set of solder balls 120 is coupled to a printed circuit board (PCB) (not shown).
Conventional integrated packages, such as the one described in FIG. 1, have certain limitations and downsides. For example, the substrate 102 of the integrated package 100 of FIG. 1 is typically made of an organic laminate (e.g., rigid or flexible), or a silicon (Si) interposer. The use of such materials as a substrate creates design problems when attempting to manufacture low profile integrated package. That is, these materials create substantial design penalty due to their manufacturing limitations. In particular, these materials make it impossible or cost-prohibitive to provide a low profile integrated package that includes multiple dies, where the integrated package takes up as little real estate as possible.
Moreover, the use of solder balls as a coupling method between a die and a substrate limits the density of the connection that can exist between a die and a substrate, as the minimum spacing required between solder balls is often greater than the minimum spacing required between traces and/or vias on a substrate.
Therefore, there is a need for a cost effective integrated package that has a low profile but also takes up a little real estate as possible. Ideally, such an integrated package will also provide higher density connections with the dies.